THE EVERYDAY ENGINEERING TOOLKIT
Engineering calculations,
made simple.
From first principles to your next design decision. Free mechanical engineering calculators that show the work.
A CLEARER PATH FROM INPUT TO INSIGHT.
YOUR ENGINEERING TOOLKIT
Less setup. More solving.
Find the right equation.
Understand every result.
10 calculators · Free to use, no sign-up
Columns & stability
Euler Column Buckling
Calculate elastic critical load, buckling stress and slenderness for an ideal column with common end restraints.
Open calculator →Columns & stability
Johnson Parabolic Buckling
Evaluate the Johnson parabola and automatically switch to Euler above the transition slenderness.
Open calculator →Stress & fatigue
Modified Goodman Fatigue
Estimate fatigue safety factor from tensile mean stress, alternating stress and a corrected endurance limit.
Open calculator →Beams & deflection
Simply Supported Beam
Find reactions, bending stress and maximum deflection for a rectangular beam under a central point load.
Open calculator →Beams & deflection
Cantilever Beam
Calculate fixed-end moment, maximum stress and tip deflection for a rectangular cantilever with an end load.
Open calculator →Power transmission
Circular Shaft Torsion
Compute polar inertia, maximum shear stress and twist for a solid circular shaft under torque.
Open calculator →Power transmission
Spur Gear Ratio
Calculate speed reduction, ideal torque multiplication and rotation direction for a pair of external spur gears.
Open calculator →Fasteners & joints
Bolt Preload
Estimate a bolt preload and tightening torque from proof strength, tensile stress area and nut factor.
Open calculator →Stress & fatigue
Axial Deformation
Determine stress, strain and elongation or shortening of a uniform bar under an axial force.
Open calculator →Stress & fatigue
Thin-Walled Pressure Vessel
Estimate cylinder hoop and longitudinal membrane stress and check the thin-wall radius-to-thickness ratio.
Open calculator →BUILT ON FIRST PRINCIPLES
Know what’s behind
the number.
Model your problem
Choose a calculator, check its assumptions, and enter the geometry, loads and material properties.
See results as you work
Inputs convert to consistent SI units. Pure equations run locally, with immediate validation and results.
Check the reasoning
Explore each formula, worked example and limitation before applying a result to your design.
These tools provide theoretical estimates for learning and preliminary analysis. Independently verify inputs, model suitability and results before safety-critical use.